The amount of carbon dioxide in the atmosphere, the gas that drives global warming, is greater by more than a quarter on any previous high in the last 650,000 years, according to a European study.

Analysis of air bubbles trapped in ice taken from east Antarctica has revealed the stark comparison and the findings will be added to evidence of human interference in the Earth´s climate, which has been collected for next week´s United Nations´ conference on global warming in Montreal, Canada.

The latest sample, or ice core, extends previous records by 210,000 years. It was obtained by the European Project for Ice Coring in Antarctica, and the findings are published in the journal Science today. The scientists, working in severe weather conditions, used a four-inch wide drill bit, in 10ft sections, to bring up ice that was deposited by snows that fell up to 650,000 years ago.

The analysis showed that today´s atmospheric carbon dioxide concentration, at 380 parts per million, is already 27 per cent greater than previous highs, said Prof Thomas Stocker of the University of Bern, Switzerland. "We have added another piece of information showing that the timescales on which humans have changed the composition of the atmosphere are extremely short compared to the natural time cycles of the climate system."

Ed Brook, a professor of geosciences at Oregon State University, who analysed the research, said: "Not long ago we thought that previous ice studies which go back about 500,000 years might be the best we could obtain. Now we have a glimpse into the past of up to 650,000 years, and we believe it may be possible to go as much as one million years or more."

He added: "The levels of primary greenhouse gases such as methane, carbon dioxide and nitrous oxide are up dramatically since the Industrial Revolution, at a speed and magnitude that the Earth has not seen in hundreds of thousands of years. There is now no question this is due to human influence."

• Ocean levels are rising by two millimetres per year compared with one millimetre annually for the last several thousand years, according to Prof Kenneth Miller of Rutgers, The State University of New Jersey. "With solid historical data, we know it is definitely a recent phenomenon," he said.